Class Solution


  • public class Solution
    extends Object
    1053 - Previous Permutation With One Swap.

    Medium

    Given an array of positive integers arr (not necessarily distinct), return the lexicographically largest permutation that is smaller than arr, that can be made with exactly one swap (A swap exchanges the positions of two numbers arr[i] and arr[j]). If it cannot be done, then return the same array.

    Example 1:

    Input: arr = [3,2,1]

    Output: [3,1,2]

    Explanation: Swapping 2 and 1.

    Example 2:

    Input: arr = [1,1,5]

    Output: [1,1,5]

    Explanation: This is already the smallest permutation.

    Example 3:

    Input: arr = [1,9,4,6,7]

    Output: [1,7,4,6,9]

    Explanation: Swapping 9 and 7.

    Constraints:

    • 1 <= arr.length <= 104
    • 1 <= arr[i] <= 104
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • prevPermOpt1

        public int[] prevPermOpt1​(int[] arr)